Flowering Plants

Chapter 25 Notes

Angiosperms

• Phylum Anthophyta• Anthus “flower” phyt “plant”• 300,000+ species• Earth’s Dominant Plants

Flowering Plants

• Like gymnosperms:– Flowering plants have vascular tissues

and produce seeds – Heterosporous – megaspores and

microspores

• Unlike gymnosperms:–Ovules of flowering plants are enclosed

within an ovary

KEY TERMS

• OVULE – Structure in the ovary that contains a

female gametophyte and develops into a seed after fertilization

• OVARY – Base of a carpel or fused carpels that

contains ovules and develops into a fruit after fertilization

Orange Fruit Development

The Function of Fruits

• Protects seeds as they grow and mature

• Seed Dispersal

Flower Parts

Female Parts

The Pistil – 1+ Carpels• Stigma - sticky• Style – the neck

connecting stigma to ovary

• Ovary – houses ovules (each contains 1 egg)

Male Parts

The Stamen• Anther – produces

pollen grains• Filament - stalk

Ecology and Economy

• Our survival as a species depends on flowering plants –Major food crops

• Products – Cork, rubber, tobacco, coffee, chocolate,

aromatic oils for perfumes – Valuable lumber– Fibers and medicines– Clothing

Economic Botany

• Subdiscipline of botany that deals with plants of economic importance–Most of these are flowering plants

KEY TERMS

• COTYLEDON – The seed leaf of a plant embryo, which

may contain food stored for germination

KEY TERMS• MONOCOT – Seeds contain a

single cotyledon

–Monocots have floral parts in threes

–Monocots include grasses, orchids, irises, onions, lilies, palms• Mostly Herbaceous

KEY TERMS• EUDICOT – Seeds contain two

cotyledons

– Eudicots have floral parts in fours or fives

– Eudicots include oaks, roses, mustards, cacti, blueberries, sunflowers

Life Cycle

• Flowering plants undergo an alternation of generations:– Sporophyte generation is larger and

nutritionally independent– Gametophyte generation is reduced to

only a few microscopic cells

KEY TERMS

• DOUBLE FERTILIZATION – A process in the flowering plant life

cycle in which there are two fertilizations

– One results in formation of a zygote

– Second results in formation of endosperm

KEY TERMS

• ENDOSPERM – The 3n nutritive tissue formed at

some point in the development of all angiosperm seeds

– Formed by double fertilization• The two polar nuclei fuse with the second

sperm cell

Life Cycle: Flowering Plants

Pollen Grains

Adaptations of Flowering Plants

• Reproduce sexually by forming flowers• Form seeds within fruits after double

fertilization• Efficient water-conducting vessel

elements in xylem • Efficient carbohydrate-conducting

sieve-tube elements in phloem• Have pollen grains transported by wind,

water, insects, other animals

KEY TERMS

• APOMIXIS – A type of reproduction

– Fruits and seeds are formed asexually

– No fusion of gametes

– Embryo is genetically similar to parent

– Plants that reproduce by apomixis: dandelions, citrus trees, blackberries, garlic, certain grasses.

Adaptability of Flowering Plants

KEY TERMS

• BASAL ANGIOSPERM – Group of angiosperms thought to be

ancestral to all other flowering plants

• CORE ANGIOSPERM – Group including most angiosperm species

– Divided into three subgroups: magnoliids, monocots, and eudicots

KEY TERMS

• MAGNOLIID – One of the groups of flowering plants

– Core angiosperms once classified as “dicots,” but molecular evidence indicates they are neither eudicots nor monocots

– Includes species in magnolia, laurel, and black pepper families, several related families

It’s Chart Time!Woo Hoo!

Flowering Plant Families 1

• More than 300 families

• Magnolia family– Important ornamentals and source of

timber– Examples: southern magnolia, tuliptree

Magnolia Family

Flowering Plant Families 2

• Walnut family– Provides nuts for food, wood for furniture – Examples: English walnut, black walnut,

pecan

• Cactus family – Important as ornamentals– Examples: prickly pear, Christmas cactus

Walnut Family

Fig. 25-10b, p. 498

Fig. 25-10c, p. 498

Cactus Family

Flowering Plant Families 3• Mustard family–Many important food crops– Examples: cabbage, broccoli, cauliflower,

turnip, mustard

• Rose family– Commercially important fruits and

ornamentals– Examples: apple, pear, plum, cherry,

apricot, peach, strawberry, raspberry, rose

Mustard Family

Mustard Family

Mustard Family

Mustard Family

Rose Family

Rose Family

Rose Family

Flowering Plant Families 4

• Pea family– Important food crops– Examples: garden pea, chick pea, green

bean, soybean, lima bean, peanut, red clover, alfalfa

Pea Family

Pea Family

Pea Family

Flowering Plant Families 5

• Potato family– Important food crops and chemicals used

as drugs– Examples: potato, tomato, green pepper,

eggplant, petunia, deadly nightshade (belladonna)

Potato Family

Flowering Plant Families 6

• Pumpkin family– Food crops– Examples: pumpkins, melons, squashes,

cucumbers, cantaloupe, honeydew, muskmelon, cucumber, watermelon

Pumpkin Family

Pumpkin Family

Flowering Plant Families 7

• Sunflower family– One of the largest families of flowering

plants– Examples: chrysanthemums, marigolds,

sunflowers, daisies, and some food plants such as lettuce, globe artichokes

Sunflower Family

Flowering Plant Families 8

• Grass family–Most important family of flowering

plants from the human standpoint– Examples: rice, wheat, corn, oats,

barley, rye, sugarcane, bamboo

Grass Family

Flowering Plant Families 9

• Orchid family– One of the largest families of flowering

plants; contains a greater variety of flowers than any other family

– Example: the vanilla orchid

• Agave family– Best known for ornamentals– Examples: century plant, sisal hemp,

bowstring hemp

Orchid Family